Objective:
1. Define the critical environmental and biological factors such as temperature, moisture content, organic matter content/composition, and nutrient content affecting emissions of odor compounds, greenhouse gases, and ammonia from beef cattle feedlot surfaces.
2. Measure the effects of critical environmental and biological factors identified in Objective 1 on nutrient transport of N, P, and indicator microorganisms from beef cattle feedlot surfaces.
3. Determine the potential for emissions of pathogenic, fecal indicator microorganisms, nutrient and odor compounds in wastewater, soil and air during and after spray wastewater application.
4. Evaluate alternative treatment technologies such as constructed wetlands, cattle feedlot runoff systems, and water treatment technologies to reduce or eliminate the occurrence, transmission, or persistence of manure-borne pathogens and excessive nutrients (N and P) and other constituents (biological oxygen demand, pH, and total suspended solids).

Approach:
Experiments will be conducted in the field and in the laboratory to evaluate gas emissions, nutrient transport, and microbial transport and fate associated with specific types of confined animal feeding operations and wastewater treatment processes. Specific areas within beef cattle feedlot pens will be identified that disproportionately emit gases (odor compounds, ammonia, and greenhouse gases) or have a large potential for nutrient runoff through the use of flux chambers and gas chromatography and by the use of artificial rainfall simulators. Flux chambers, mass losses from soil, and bioaerosol sampling will be used to determine the loss of nutrients, odor compounds, and the potential to disseminate manure-borne microorganisms in multi-year studies at field sites where swine wastewater is center pivot applied to agricultural fields. Standard microbiological techniques will be used to determine the prevalence of manure-borne microorganisms after alternative treatments have been used to treat wastewater.